wireless transmission of square wave

[hitesh joshi]

Hey guys i want help in designing a circuit to transfer square wave pulse fed on transmitting end through a frequency generator and get it on receiving end and check it on an oscilloscope.

 

[BradtheRad]

Do you wish to use AM (amplitude modulation) or FM (frequency modulation)?

 

[hitesh joshi]

Thanks for replying, I would like to use fm modulation...can u provide some help..

 

[BradtheRad]

There are simple FM modulator circuits, based on 1 or 2 transistors.

Adjust your transmitter so that when your waveform is at zero, it broadcasts a low frequency.

Have it broadcast a high frequency when the waveform is high.

The carrier frequency should be many times the square wave frequency. The carrier frequency should be so high that it has sufficient resolution to show the details you wish to see in the received signal.

 

[hitesh joshi]

i have a RF module working at 433mhz.heres the link
https://www.google.co.in/url?sa=t&r...=N38TBPVYKjOH5hCM8E5HQQ&bvm=bv.54176721,d.bmk

And how to make this simple FM modulator circuits, based on 1 or 2 transistors.

thanks..
hitesh

- - - Updated - - -

i searched online about simple FM modulator circuits..heres a attached link..there are lot of them..which is the best and how to transmit a square wave with this and receive at the receiving end sothat it can be displayed on oscilloscope.

http://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CCwQFjAA&url=http%3A%2F%2Fcircuit-zone.com%2F%3Fcat%3Dfm_transmitters&ei=gexfUuySJY2RrAe6s4DAAQ&usg=AFQjCNHg5qFrIltvkYIc6hAn0Vr53bZ_lQ&sig2=tiqt8s8h6PTsqkLa-AOXOQ&bvm=bv.54176721,d.bmk

thanks
hitesh

- - - Updated - - -

i searched online about simple FM modulator circuits..heres a attached link..there are lot of them..which is the best and how to transmit a square wave with this and receive at the receiving end sothat it can be displayed on oscilloscope.

http://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CCwQFjAA&url=http%3A%2F%2Fcircuit-zone.com%2F%3Fcat%3Dfm_transmitters&ei=gexfUuySJY2RrAe6s4DAAQ&usg=AFQjCNHg5qFrIltvkYIc6hAn0Vr53bZ_lQ&sig2=tiqt8s8h6PTsqkLa-AOXOQ&bvm=bv.54176721,d.bmk

thanks
hitesh

 

[BradtheRad]

A large assortment of schematics is at this link:

https://www.bing.com/images/search?...orm=QBIR&pq=fm+transmitter+c&sc=8-16&sp=1&sk=

Many have a mic input, followed by a stage to increase gain. However you may not need to increase the amplitude of your square wave.

The FM modulation is done by a single transistor with an LC tank circuit nearby, plus a capacitor and antenna.

It is up to you to experiment and discover which component parameters will work best with your signal.